Periodontal inflammation is one of the most common diseases of the adult population. Periodontal inflammation is induced by the dental plaque, a mixture of bacteria embedded in an adhesive matrix, present on the tooth surface particularly at the interdental spaces and near the gums. The initial pathological reaction to the plaque, called gingivitis, is expressed by the soft gum tissue as redness, bleeding, swelling, bad breath and sour taste. Later, over a period of several years, the gum disease progresses and causes destruction of the tooth supporting bone, leaving a pathologic space between the tooth root and the gum. This space is the periodontal pocket. The plaque extends into the pockets, from which it cannot be removed by conventional oral hygiene methods, such as brushing and flossing. This plaque induces further damage, increasing the pocket size in depth and width, with eventual tooth loss. In addition to the gingivitis, plaque present in the interdental space also causes interproximal tooth decay.
Since the implication of plaque in the development of dental diseases, the majority of plaque control devices introduced over the past decades have been developed for supragingival plaque removal. Supragingival plaque can be effectively removed by brushing and flossing, but most brushing and flossing devices are restricted by physical restraints that limit their ability to extend far enough below the gingival margin. The configuration of tooth picks, pipe cleaners, interdental brushes and other interdental cleaning aids also limits the effect of these devices on subgingival plaque. Furthermore, antiplaque agents used as mouth rinses affect only supragingival plaque unless such agents are introduced below the gingival margin with an irrigating device. Oral irrigators allow practitioners and patients access to subgingival areas in order to disrupt the plaque that proliferates at these sites.
Irrigation can be defined simply as "the flushing of a specific site or area with a stream of fluid delivered by an irrigator". In 1968, the first powered oral irrigation device, WaterPik.RTM. (Teledyne WaterPik), was accepted by the American Dental Association for its ability to remove food particles and debris from interdental areas and below the gum line. This device was widely recommended, particularly for orthodontic and prosthodontic patients. However, research was unable to establish a definitive relationship between the presence of debris and periodontal disease and found no evidence that irrigation with WaterPik.RTM. could significantly reduce plaque. Subsequent research utilizing antimicrobial solutions delivered by an oral irrigator equipped with a fine probe, has helped to establish oral irrigation as a useful procedure for plaque control, especially for "site specific" therapeutic approaches that require direct delivery of antimicrobial solutions into the affected sulcus or pocket, and has expanded the usefulness of the irrigator in preventative care, beyond its application as a mechanism to simply flush away debris.
Researchers of general preventive techniques, dental hygiene educators as well as various practitioners, have maintained that oral irrigation is an effective adjunctive plaque control therapy throughout the course of periodontal treatment, from initial plaque removal instruction through maintenance. Furthermore, experts gathered at the April 1991 meeting of the International Association of Dental Research in Acapulco, Mexico, agreed that the use of antimicrobial solutions applied with oral irrigation systems exhibits high promise in the site specific treatment of periodontal conditions.
Irrigators designed for home care by the patient consist of a power driven pump or flexible syringe bulb and a tip. The early irrigator tips, designed for supragingival removal of debris were too large to penetrate the interdental space and gingival sulcus of patients with undisrupted gum architecture or periodontal pockets. In addition, the motor driven pumps deliver a powerful stream that causes undesirable enforcement of debris and microorganisms into the dental tissues. Subgingival irrigation devices, introduced into the dental market over the past decade, are capable of delivering medicaments directly to the site of the periodontal infection. This form of therapy can effectively remove bacterial plaque in sites inaccessible to brushing, flossing and other mechanical manipulations [a variety of available irrigation devices can be found in Dental Products Report.RTM. Europe (also published in the U.S.A.); MEDEC Dental Communications, A Division of Medical Economics Publishing Company, Inc., October 1991].
However, one of the main drawbacks of oral hygiene techniques used for arrest or prevention of periodontal diseases, particularly irrigation, is patient compliance, since the patient should maintain routine, day-by-day treatment. A great deal of the noncompliance can be attributed to the non-handiness of most available oral irrigators.
U.S. Pat. No. 5,127,831, corresponding to co-pending Israel Patent Application No. 98355, discloses a novel irrigation probe, particularly suitable for use by a patient. Conventional irrigation devices, like blunt, rigid metal needles, are also used for irrigation, by trained personnel [e.g. Soh, L. L., et al., J. Clin. Periodontol. 9: 66-74 (1982); J. G. L. Khoo and H. N. Newman, J. Periodont. Res. 18: 607-619 (1983)]. Another dental irrigation needle is disclosed in U.S. Pat. No. 4,993,941. Additionally, IMAX.RTM. Periotips.RTM. (SDI Group, Inc., IL U.S.A.) are used for in-office professional subgingival irrigation.
All of the known prior art irrigation probes can be used with various pumping devices containing the irrigation fluid, which may be water or medically compatible solutions. These devices include different manual and automatic syringes, spray injectors and mechanically or electrically driven pump systems. The known pumping devices, particularly syringes, are mostly designed for in-office use by trained personnel.
Another pumping device, stated to be suitable for use by a patient, is sold under the name Luer Syrette.RTM. (Perio Dental, Inc., Colorodo USA). This pumping device consists of a compressible bulb, which has a narrow opening, and a hollow shaft. One end of the shaft can be sealing fitted into the opening is the bulb, the other end has a luer lock for connecting the irrigation probe. This Luer Syrette.RTM. in only operable when held in an upright position. Thus, in order to irrigate lower jaw sites, or other sites which are difficult to reach, an elongate extension tube is used, connecting said luer lock with the irrigation probe, to enable the attending dentist or the patient to reach all subgingival pockets, while maintaining the Luer Syrette.RTM. in the upright position. To achieve the upright position, both hands of the user are engaged which is a drawback since one hand should preferably be free, to push aside the lip/s or cheek/s, to expose the target site. In addition, the structure of the Luer Syrette.RTM. is rather complex, since it requires the inclusion of an anti-suction valve, preventing suction of the irrigation fluid back into the bulb when pressure on the bulb is released. Moreover, the bulb opening is narrow and the bulb is filled with the irrigation fluid by suction from a larger container. Also washing of the bulb with water between uses is achieved by suction. Evidently, the fact that the bulb can only be operated when in an upright position is a major drawback, particularly when considering the anatomy of the mouth, and especially when used by the patient.
The present invention intends to overcome the described drawbacks, essentially by providing an irrigation device which is equipped with a non-kinking weighted dip tube, which is submerged in the irrigation fluid irrespective of the spatial position in which the irrigator is held.
Various fluid dispensing devices comprising a weighted dip tube assembly, some of them non-kinking tubes, which ensures that the free end of the dip tube is always submerged in the fluid to be dispensed are known. Such fluid dispensing devices are described, for example, in UK Patent Applications Nos. 902,114, 1,008,733, 2,136,057, 2,217,394 and 2,234,555, U.S. Pat. Nos. 2,978,152, 3,088,680, 3,211,349, 3,490,656 and 3,667,655, DE 36 36 409 and French Patent Applications Nos. 1,479,528, 1,565,071, 2,101,505 and 2,437,246. However, none of the dispensers disclosed in these publications is intended for dental use, and in all of the disclosed dispensers, the container is rigid and the pressurized fluid is dispensed by aerosol means. Moreover, the prior art dispensers appear to be only suitable for one-time use and cannot be refilled.